Rhythm Pharmaceuticals’ Chief Financial Officer, Hunter C. Smith, sold 23,072 shares on Aug. 31, 2026 at $104.59 per share, for a total of about $2.41 million. The company indicated the sale was made under a pre-scheduled Rule 10b5-1 trading plan, meaning the timing and amount are typically set in advance and can reduce the informational value of the trade compared with a discretionary, spur-of-the-moment sale. CFO trades can draw attention because finance chiefs often have a broad view of a company’s budgeting, cash position, and reporting process. That said, sales can occur for many non-business reasons such as taxes or diversification, and a planned 10b5-1 sale is generally viewed as more routine than an open-market sale made at the insider’s discretion. Over the past 30 days, this filing is the only reported insider transaction for RYTM. With no cluster of recent insider buying or multiple executives selling in the same period, the available data points to a single, plan-based sale rather than a broader pattern of insider activity.